#!/usr/bin/env python
def trapezium(x, y):
    for m in range (0, y):
        a = ""
        for n in range (0, y-1-m):
            a += " "
        for s in range(0, x+2*m):
            a += "*"
        print(a)

a = int(input("x:"))
b = int(input("y:"))
trapezium(a,b)

